Vacuum pan



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VACUUM PAN 7 Filed Sent. 13, 1920 wvmtoz God 4g 23 9! 5):

latented Dec. 4, 1923.

UNITED STATES wean PATENT caries.

GODFREY ENGEL, SR., BROOKLYN, NEW YORK, ASSIGNOR TO BUFFALO FOUNDRY &

V MACHINE (10., OF BUFFALO, NEW YORK, A CORPORATION OF NEW YORK.

VACUUM PAN.

Application filed September 13, 1920. Serial No. 409,762.

To all whom it may concern:

Be it known that I, GODFREY ENGEL, Sn, a citizen of the United States,anda resident of Brooklyn, Kings County, and State of New York, haveinvented certain new and useful Improvements in Vacuum Pans, of whichthe following is'a specification.

My-invention relates to apparatus in the nature of vacuum pans, used forevaporating 0 and for heating and cooling purposes.

An important object of the invention is to secure an eifective.circulation of the material under treatment, and to. accomplish this byrelatively simple and entirely prac-- 5 tical mechanism.

The invention involves certain novel features of construction,combinations and relations of parts, of which 'a typical embodiment isdisclosed in the accompanying drawing, the single view representing avertical section of the apparatus.

The casing or shell of the apparatus is designated 5, the same beingmade of a size and shape to best suit the purposes for which it isintended.

In the bottom portion of the pan, there is provided a calandria, thesame being shown as of the novel construction disclosed in my co-pendingapplication, Serial No.

374,659, and consisting of upper and lower inverted conical tube sheets6 and 7, connected by the downwardly and outwardly inclined tubes 8. Thelower tube sheet 7 is shown as of larger internal andexternal diameterand the two sheets are shown as connected together at the center by aconical wall 9, forming an upwardly converging central passage. I

In dealing with the more heavy liquids,

' I have found that the action'is retarded by the viscosity of thematerial and that under certain circumstances, the difierence intemperature is not sufiicient to efiect a proper circulation through andaboutthe calandria tubes.

To overcome this difliculty, I mount in the bottom of the pan below thecentral calandria passage, a forced circulation 'creatinclined tubes andacross the inclined tube sheets and the material is prevented from ingdevice shown in the form of a propeller .10 carried by the shaft 11 andconsisting of a series of curved impeller blades 12.- This propeller isshown as of generally conical shape, arranged with the'apex thereofprojecting up into the conical calandria .pas-

sage and the lower edges of the blades are shown as connected for thegreater portion of their length by a web 13.

The propeller shaft is shown as driven through bevel gearing 14 from apower shaft 15 and a step bearing of novel construction is illustratedas provided for the lower end of the vertical propeller shaft. This stepbearing consists of a socket 16 provided in a suitable supportingbracket 17, for receiving the lower end of the propeller shaft andforming the seat for the two bearingv segments 18, 19 which surround thelower end of the shaft and are formed with an upwardly convergent boreto receive the correspondingly shaped upwa dly convergent lower endportion 20 of the shaft.

The bearing segments are indicated as socured against removal from orshiftingin their seat by a set screw 21. This relatively simpleconstruction, it will be observed, provides a thrust bearing in which apart of the bearing members serve to prevent the shaft from being liftedout of its seat.

The bottom wall of the pan beneath the calandria is indicated as ofgenerally inverted conical shape, inclined inwardly and downwardlytoward the ends of the propeller blades, as shown at 22, and thatportion of the bottom of the pan which is located beneath the body ofthe propeller is shown as inclined upwardly. This promotes the flow tothe propeller and up through the central calandria passage.

The propeller is driven at the proper speed to effect the desired rateof circulation. For heating and evaporating urposes, the propeller isrotated to pro uce a downward.

circulation through the center of the calandria and u through the tubes,heat being supplied to the calandria as by means of steam in the usualway. Where the apparatus is to be used for cooling purposes, thepropeller is driven in the reverse direction, or designed to eflect areverse flow, that is, down through the tubes and up through the centerof the calandria. In either event, the fluid is positively circulatedthrough the lodging on either the sheets or in the tubes, both by reasonof the inclination of these parts and because of the positivecirculation produced by the propeller. With this epparatus relativelyrapid and uniform evaporation and coollng effects are readilyaccomplished.

The blades of the propeller in the illustration are shown connectedatthe rim b a flange 23 which stands substantially in line with thecentral circulating passage 'of the calandria, which serves to promotethe circulation. The propeller furthermore is shown as having its bladesextending over the outlet passage 24. This is an important improvementin that it causes the blades to expel the material during discharge ofthe an.

at I claim is: 1. In apparatus of the character disclosed,

a casing, a calandria therein having an n right circulating passage withdownward y and outwardly inclined tubes grouped thereabout and apropeller in the bottom of the casing in line with the circulatingpassage for positivel circulating fluid in the casing through-saipassage and through the inclined tubes. 7

2. In apparatus of the character disclosed, a casing provided with anoutlet in the bottomthereof, a calandria in thecasing having an uprightcirculating passage therethrough with inclined tubes grouped about thesame and a propeller in the lower portion of the casing in line with thecirculating passage for positively circulating fluid through the passageand inclined tubes and having blades directly over and traversing theoutlet in the bottom of the casing to assist in the discharge of thecontents of the a casing,

3. In apparatus of the character described, a casing, a calandria insaid casing having an upwardly convergent circulating passagetherethrough and a propeller in' the bottom of the casing beneath thecalandria and hav-- ing a conica portion projecting up into the.

convergent passage aforesaid. v

4. In apparatus of he character disclosed, a casing, a calandria in saidcasing having upper and lower tube sheets inclined downwardliy towardthe center thereof and connecte at the center by'al'down-take, withdownwardly and outwardly inclined'tubes connecting said sheets, thebottom of the a casing, a calandria therein having inclined tube sheetsconnected by inclined tubes,'said.

calandria having a central circulating passage therethrough and apropeller in the casing for forcing a circulation of fluid through theinclined tubes andthrough the central calandria-passage.

In witness whereof, I have hereunto set my .hand this 8th da of Setember, 1920.

GODl REY NGEL, SR.

